Transition state theory for wave packet dynamics. II. Thermal decay of Bose-Einstein condensates with long-range interaction

We apply transition state theory to coupled Gaussian wave packets and calculate thermal decay rates of Bose-Einstein condensates with additional long-range interaction. The ground state of such a condensate is metastable if the contact interaction is attractive and a sufficient thermal excitation may lead to its collapse. The use of transition state theory is made possible by describing the condensate within a variational framework and locally mapping the variational parameters to classical phase space as has been demonstrated in the preceding paper [A. Junginger, J. Main, and G. Wunner, submitted to J. Phys. A]. We apply this procedure to Gaussian wave packets and present results for condensates with monopolar 1/r-interaction comparing decay rates obtained by using different numbers of coupled Gaussian trial wave functions as well as different normal form orders.Comment: 14 pages, 4 figures, submitted to J. Phys.

Transition state theory for wave packet dynamics. I. Thermal decay in metastable Schr\"odinger systems

We demonstrate the application of transition state theory to wave packet dynamics in metastable Schr\"odinger systems which are approached by means of a variational ansatz for the wave function and whose dynamics is described within the framework of a time-dependent variational principle. The application of classical transition state theory, which requires knowledge of a classical Hamilton function, is made possible by mapping the variational parameters to classical phase space coordinates and constructing an appropriate Hamiltonian in action variables. This mapping, which is performed by a normal form expansion of the equations of motion and an additional adaptation to the energy functional, as well as the requirements to the variational ansatz are discussed in detail. The applicability of the procedure is demonstrated for a cubic model potential for which we calculate thermal decay rates of a frozen Gaussian wave function. The decay rate obtained with a narrow trial wave function agrees perfectly with the results using the classical normal form of the corresponding point particle. The results with a broader trial wave function go even beyond the classical approach, i.e., they agree with those using the quantum normal form. The method presented here will be applied to Bose-Einstein condensates in the following paper [A. Junginger, M. Dorwarth, J. Main, and G. Wunner, submitted to J. Phys. A].Comment: 21 pages, 3 figures, submitted to J. Phys.

PERTANGGUNGJAWABAN ATAS PENGRUSAKAN DAN PENCEMARAN LINGKUNGAN LAUT DI LINTAS BATAS NEGARA MENURUT INSTRUMEN HUKUM INTERNASIONAL

Tujuan dilakukannya peneltian ini adalah untuk mengetahui bagaimana ketentuan hukum dalam kaitannya dengan pencemaran dan pengrusakan lingkungan laut lintas batas Negara dan bagaimana upaya negara meminta pertanggung jawaban atas pengrusakan dan pencemaran lingkungan laut di lintas batas Negara. Dengan menggunakan metode peneltian yuridis normatif, disimpulkan: 1. Indonesia mengambil tindakan tegas dalam kasus perusakan dan pencemaran lingkungan laut yang terjadi di jalur lintas batas negaranya. Dalam kasus ini Indonesia berhak mendapat kompensasi ganti kerugian dari pelaku pencemaran lingkungan laut yang terjadi wilayah perairan Indonesia, bahkan dalam ketentuan hukum internasional juga sudah diatur mengenai setiap Negara yang melakukan perbuatan melanggar aturan hukum internasional harus mendapatkan sanksi dan dapat memberikan ganti kerugian terhadap Negara yang menjadi dampak dari pencemaran lingkungan laut tersebut. Dalam kasus seperti demikian sangatlah penting untuk mendapatkan perhatian penuh dari pihak pemerintah internasional untuk segera menangani kasus tersebut agar supaya Negara yang menjadi pelaku pencemaran lingkungan laut itu langsung membayar kompensasi ganti rugi kepada Negara yang menjadi korban pencemaran lingkungan lautnya. 2. Upaya Negara Indonesia dalam meminta pertanggungjawaban atas perusakan dan pencemaran lingkungan laut di wilayah yurisdiksi Negara Indonesia adalah dengan cara melakukan pengajuan kepada pemerintah internasional dalam hal ini melalui pengadilan internasional yang menangani kasus atas perusakan dan pencemaran lingkungan laut di lintas batas Negara. Indonesia mempunyai kewenangan sebagai Negara pantai untuk dapat mengajukan ganti rugi kepada Negara pelaku pencemaran itu menurut hukum nasionalnya. Agar supaya dalam kasus ini benar-benar pihak merupakan pelaku pencemar dapat mematuhi setiap prosedur yang berlaku baik dalam hukum internasional maupun hukum nasional di wilayah yurisdiksi negara yang menjadi korban pencemaran tersebut.Kata kunci: Pertanggungjawaban, Pengrusakan dan Pencemaran, Lingkungan Laut,  Lintas Batas Negara, Instrument Hukum Internasional

Non-perturbative Interband Response of InSb Driven Off-resonantly by Few-cycle Electromagnetic Transients

Intense multi-THz pulses are used to study the coherent nonlinear response of bulk InSb by means of field-resolved four-wave mixing spectroscopy. At amplitudes above 5 MV/cm the signals show a clear temporal substructure which is unexpected in perturbative nonlinear optics. Simulations based on a two-level quantum system demonstrate that in spite of the strongly off-resonant character of the excitation the high-field pulses drive the interband resonances into a non-perturbative regime of Rabi flopping.Comment: 4 pages, 4 figure

Cost optimization of biofuel production – The impact of scale, integration, transport and supply chain configurations

This study uses a geographically-explicit cost optimization model to analyze the impact of and interrelation between four cost reduction strategies for biofuel production: economies of scale, intermodal transport, integration with existing industries, and distributed supply chain configurations (i.e. supply chains with an intermediate pre-treatment step to reduce biomass transport cost). The model assessed biofuel production levels ranging from 1 to 150 PJ a−1 in the context of the existing Swedish forest industry. Biofuel was produced from forestry biomass using hydrothermal liquefaction and hydroprocessing. Simultaneous implementation of all cost reduction strategies yielded minimum biofuel production costs of 18.1–18.2 € GJ−1 at biofuel production levels between 10 and 75 PJ a−1. Limiting the economies of scale was shown to cause the largest cost increase (+0–12%, increasing with biofuel production level), followed by disabling integration benefits (+1–10%, decreasing with biofuel production level) and allowing unimodal truck transport only (+0–6%, increasing with biofuel production level). Distributed supply chain configurations were introduced once biomass supply became increasingly dispersed, but did not provide a significant cost benefit (<1%). Disabling the benefits of integration favors large-scale centralized production, while intermodal transport networks positively affect the benefits of economies of scale. As biofuel production costs still exceeds the price of fossil transport fuels in Sweden after implementation of all cost reduction strategies, policy support and stimulation of further technological learning remains essential to achieve cost parity with fossil fuels for this feedstock/technology combination in this spatiotemporal context

Coaxial multi-mode cavities for fundamental SRF research in an unprecedented parameter space

Recent developments in superconducting radio-frequency (SRF) research have focused primarily on high frequency elliptical cavities for electron accelerators. Advances have been made in both reducing RF surface resistance and pushing the readily achievable accelerating gradient by using novel SRF cavity treatments including surface processing, custom heat treatments, and flux expulsion. Despite the global demand for SRF based hadron accelerators, the advancement of TEM mode cavities has lagged behind. To address this, two purpose-built research cavities, one quarter-wave and one half-wave resonator, have been designed and built to allow characterization of TEM-mode cavities with standard and novel surface treatments. The cavities are intended as the TEM mode equivalent to the 1.3GHz single cell cavity, which is the essential tool for high frequency cavity research. Given their coaxial structure, the cavities allow testing at the fundamental mode and higher harmonics, giving unique insight into the role of RF frequency on fundamental loss mechanisms from intrinsic and extrinsic sources. In this paper, the cavities and testing infrastructure are described and the first performance measurements of both cavities are presented

Current and future technical, economic and environmental feasibility of maize and wheat residues supply for biomass energy application:Illustrated for South Africa

AbstractThis study assessed the feasibility of mobilising maize and wheat residues for large-scale bioenergy applications in South Africa by establishing sustainable residue removal rates and cost of supply based on different production regions. A key objective was to refine the methodology for estimating crop residue harvesting for bioenergy use, while maintaining soil productivity and avoiding displacement of competing residue uses. At current conditions, the sustainable bioenergy potential from maize and wheat residues was estimated to be about 104 PJ. There is potential to increase the amount of crop residues to 238 PJ through measures such as no till cultivation and adopting improved cropping systems. These estimates were based on minimum residues requirements of 2 t ha−1 for soil erosion control and additional residue amounts to maintain 2% SOC level.At the farm gate, crop residues cost between 0.9 and 1.7 $GJ−1. About 96$ GJ−1. In the improved scenario, up to 85% of the biomass is below 1.3 $GJ−1. For biomass deliveries at the conversion plant, about 36$ GJ−1 while in the optimised scenario, about 87% is delivered below 5$ GJ−1. Co-firing residues with coal results in lower cost of electricity compared to other renewables and significant GHG (CO2 eq) emissions reduction (up to 0.72 tons MWh−1). Establishing sustainable crop residue supply systems in South Africa could start by utilising the existing agricultural infrastructure to secure supply and develop a functional market. It would then be necessary to incentivise improvements across the value chain

Biowaiver monographs for immediate release solid oral dosage forms: acetaminophen (paracetamol).

Literature data are reviewed on the properties of acetaminophen (paracetamol) related to the biopharmaceutics classification system (BCS). According to the current BCS criteria, acetaminophen is BCS Class III compound. Differences in composition seldom, if ever, have an effect on the extent of absorption. However, some studies show differences in rate of absorption between brands and formulations. In particular, sodium bicarbonate, present in some drug products, was reported to give an increase in the rate of absorption, probably caused by an effect on gastric emptying. In view of Marketing Authorizations (MAs) given in a number of countries to acetaminophen drug products with rapid onset of action, it is concluded that differences in rate of absorption were considered therapeutically not relevant by the Health Authorities. Moreover, in view of its therapeutic use, its wide therapeutic index and its uncomplicated pharmacokinetic properties, in vitro dissolution data collected according to the relevant Guidances can be safely used for declaring bioequivalence (BE) of two acetaminophen formulations. Therefore, accepting a biowaiver for immediate release (IR) acetaminophen solid oral drug products is considered scientifically justified, if the test product contains only those excipients reported in this paper in their usual amounts and the test product is rapidly dissolving, as well as the test product fulfils the criterion of similarity of dissolution profiles to the reference product

A low energy muon spin rotation and point contact tunneling study of niobium films prepared for superconducting cavities

Point contact tunneling and low energy muon spin rotation are used to probe, on the same samples, the surface superconducting properties of micrometer thick niobium films deposited onto copper substrates using different sputtering techniques: diode, dc magnetron and HIPIMS. The combined results are compared to radio-frequency tests performances of RF cavities made with the same processes. Degraded surface superconducting properties are found to correlate to lower quality factors and stronger Q-slope. In addition, both techniques find evidence for surface paramagnetism on all samples and particularly on Nb films prepared by HIPIMS